import axios, { AxiosError, AxiosRequestConfig } from 'axios';

const TOKEN_KEY = 'olons_web_session';
const DEVICE_KEY = 'olons_web_device';
const LOGIN_NOTICE_PENDING_KEY = 'olons_login_notice_pending';

const reasonMessages: Record<string, string> = {
  AUTH_REQUIRED: '登录已失效，请重新登录',
  FORBIDDEN: '当前账户无权执行此操作',
  INVALID_CREDENTIALS: '手机号或密码错误',
  ACCOUNT_ALREADY_REGISTERED: '该账户或手机号已经注册',
  REFERRAL_CODE_INVALID: '邀请码无效，请检查后重新输入',
  RATE_LIMITED: '操作过于频繁，请稍后再试',
  TASK_DISABLED: '领取功能暂未开放',
  OUTSIDE_BUSINESS_HOURS: '当前不在营业时间内',
  INSUFFICIENT_BALANCE: '可用余额不足299元，暂时无法领取',
  DAILY_LIMIT_REACHED: '今日领取次数已用完',
  PENDING_ORDER_EXISTS: '存在未完成的任务，请先处理',
  NO_TASK_AVAILABLE: '当前暂无可领取任务',
  ORDER_EXPIRED: '该任务已超时',
  ORDER_STATE_INVALID: '当前任务状态不允许此操作',
  TRADE_PASSWORD_NOT_SET: '请先设置支付密码',
  TRADE_PASSWORD_INVALID: '支付密码不正确',
  PAYMENT_ACCOUNT_FIELDS_INVALID: '绑卡信息填写不完整或格式不正确',
  QR_ATTACHMENT_INVALID: '二维码图片无效，请重新上传',
  IMAGE_INVALID: '图片格式或大小不符合要求',
  PAYMENT_ACCOUNT_INVALID: '收款账户未核验或不可用',
  WITHDRAWAL_DISABLED: '取出功能暂未开放',
  WITHDRAWAL_AMOUNT_INVALID: '取出金额不符合当前规则',
  WITHDRAWAL_DAILY_LIMIT_REACHED: '今日取出次数已用完',
  WITHDRAWAL_CHANNEL_UNAVAILABLE: '当前没有可用的取出通道',
  RECHARGE_AMOUNT_INVALID: '储入金额不符合当前通道规则',
  RECHARGE_CHANNEL_UNAVAILABLE: '当前没有可用的储入通道',
  RECHARGE_VOUCHER_INVALID: '储入凭证无效',
  SERVICE_UNAVAILABLE: '服务暂不可用，请稍后重试',
  CUSTOMER_SERVICE_NOT_FOUND: '客服已下线或不存在',
  CUSTOMER_SERVICE_NOT_BOUND: '客服账号尚未配置',
  IM_RELATION_PENDING: '好友申请已发送，请等待客服确认',
  IM_RELATION_NOT_ALLOWED: '当前无法与该客服建立会话',
  IM_SERVICE_UNAVAILABLE: '客服系统暂不可用，请稍后重试',
  INTERNAL: '服务异常，请稍后重试',
};

export interface ApiEnvelope<T> {
  code: number;
  data: T;
  message?: string;
  reason?: string;
  request_id?: string;
  server_time?: string;
}

export class MobileApiError extends Error {
  reason: string;
  status: number;

  constructor(message: string, reason = '', status = 0) {
    super(message);
    this.reason = reason;
    this.status = status;
  }
}

const client = axios.create({
  baseURL: '',
  timeout: 15000,
  headers: { Accept: 'application/json' },
});

client.interceptors.request.use((config) => {
  const token = sessionStorage.getItem(TOKEN_KEY);
  if (token) config.headers.Authorization = `Bearer ${token}`;
  config.headers['X-Request-ID'] = crypto.randomUUID?.() || `${Date.now()}-${Math.random()}`;
  config.headers['X-Device-ID'] = getDeviceID();
  return config;
});

client.interceptors.response.use(
  (response) => response,
  (error: AxiosError<ApiEnvelope<unknown>>) => {
    const status = error.response?.status || 0;
    const payload = error.response?.data;
    if (status === 401) {
      clearSession();
      const currentPath = window.location.hash.replace(/^#/, '') || '/app/home';
      if (!currentPath.startsWith('/app/auth')) {
        window.location.hash = `/app/auth?redirect=${encodeURIComponent(currentPath)}`;
      }
    }
    const reason = payload?.reason || '';
    return Promise.reject(
      new MobileApiError(
        reasonMessages[reason] ||
          payload?.message ||
          (status ? '请求失败，请稍后重试' : '网络连接失败'),
        reason,
        status
      )
    );
  }
);

export async function request<T>(config: AxiosRequestConfig): Promise<T> {
  const method = String(config.method || 'GET').toUpperCase();
  const attempts = method === 'GET' ? 3 : 1;
  let lastError: unknown;
  for (let attempt = 0; attempt < attempts; attempt += 1) {
    try {
      const response = await client.request<ApiEnvelope<T>>(config);
      if (response.data.code !== 0) {
        const reason = response.data.reason || '';
        throw new MobileApiError(
          reasonMessages[reason] || response.data.message || '请求失败',
          reason,
          response.status
        );
      }
      return response.data.data;
    } catch (error) {
      lastError = error;
      if (!shouldRetry(error, attempt, attempts)) throw error;
      await new Promise((resolve) => window.setTimeout(resolve, attempt === 0 ? 250 : 600));
    }
  }
  throw lastError;
}

function shouldRetry(error: unknown, attempt: number, attempts: number) {
  if (attempt >= attempts - 1) return false;
  if (axios.isCancel(error)) return false;
  return error instanceof MobileApiError && (error.status === 0 || error.status === 503);
}

function getDeviceID() {
  let value = localStorage.getItem(DEVICE_KEY);
  if (!value) {
    value = crypto.randomUUID?.() || `web-${Date.now()}-${Math.random().toString(36).slice(2)}`;
    localStorage.setItem(DEVICE_KEY, value);
  }
  return value;
}

export function deviceID() {
  return getDeviceID();
}

export function saveSession(token: string) {
  sessionStorage.setItem(TOKEN_KEY, token);
  sessionStorage.setItem(LOGIN_NOTICE_PENDING_KEY, '1');
}

export function clearSession() {
  sessionStorage.removeItem(TOKEN_KEY);
  sessionStorage.removeItem(LOGIN_NOTICE_PENDING_KEY);
}

export function hasSession() {
  return Boolean(sessionStorage.getItem(TOKEN_KEY));
}

export function shouldShowLoginNotice() {
  return sessionStorage.getItem(LOGIN_NOTICE_PENDING_KEY) !== '0';
}

export function completeLoginNotice() {
  sessionStorage.setItem(LOGIN_NOTICE_PENDING_KEY, '0');
}

export function idempotencyKey() {
  return crypto.randomUUID?.() || `${Date.now()}-${Math.random().toString(36).slice(2)}`;
}

export function money(value?: number, currency = 'CNY') {
  const amount = Number.isFinite(value) ? Number(value) / 100 : 0;
  return new Intl.NumberFormat('zh-CN', {
    style: 'currency',
    currency,
    minimumFractionDigits: 2,
  }).format(amount);
}

export function dateTime(value?: string) {
  if (!value) return '--';
  const date = new Date(value);
  if (Number.isNaN(date.getTime())) return '--';
  return new Intl.DateTimeFormat('zh-CN', {
    year: 'numeric',
    month: '2-digit',
    day: '2-digit',
    hour: '2-digit',
    minute: '2-digit',
    hour12: false,
  })
    .format(date)
    .replaceAll('/', '-');
}

export function safeImage(url?: string) {
  if (!url) return '';
  try {
    const parsed = new URL(url, window.location.origin);
    return parsed.protocol === 'https:' || parsed.origin === window.location.origin
      ? parsed.href
      : '';
  } catch {
    return '';
  }
}

export function errorText(error: unknown) {
  return error instanceof Error ? error.message : '操作失败，请稍后重试';
}